Exhibit 3.124


                          CERTIFICATE OF INCORPORATION
                                       OF
                        THE ELECTRONICS SOURCE BOOK, INC.

           The undersigned, in order to form a corporation for the purpose
hereinafter stated under and pursuant to the provisions of the Delaware General
Corporation Law hereby certifies that:

           FIRST: The name of the Corporation is The Electronics Source Book,
Inc.

           SECOND: The registered office and registered agent of the Corporation
is The Corporation Trust Company, 1209 Orange Street, Wilmington, New Castle
County, Delaware, 19801.

           THIRD: The purpose of the Corporation is to engage in any lawful act
or activity for which corporations may be organized under the General
Corporation Law of Delaware.

           FOURTH: The total number of shares of stock that the Corporation is
authorized to issue is 1,000 shares of Common Stock, par value $0.01 each.

           FIFTH: The name and address of the incorporator is Beverly C. Chell,
745 Fifth Avenue, Now York, New York 10151.

           SIXTH: The Board of Directors of the Corporation, acting by majority
vote, may alter, amend Or repeal the By-Laws of the Corporation.

           SEVENTH: Except as otherwise provided by the Delaware General
Corporation Law as the same exists or may hereafter be amended, no director of
the Corporation shall be personally liable to the Corporation or its
stockholders for monctary damages for breach of fiduciary duty as a director.
Any repeal or modification of this Article SEVENTH by the stockholders of the
Corporation shall not adversely affect any right or protection of a director of
the Corporation existing at the time of such repeal or modification.

           IN WITNESS WHEREOF, the undersigned has signed this Cerificate of
Incorporation on April 28, 1994.

                                                   Beverly C. Chell